PROJECT SUMMARY?Alzheimer?s Disease (AD) is expected to affect 131 million people worldwide by 2050, but as many as one-third of these cases may be prevented by targeting modifiable risk factors such as diet, physical activity, cognitive engagement, and smoking. Neurotrack Technologies, Inc. has developed a digital multi-domain lifestyle intervention for cognitive health designed to change behaviors associated with increased risk for AD. In a pilot study, this intervention supported significant behavior changes in multiple lifestyle domains, reduced depressive and anxiety symptoms, and improved performance on a composite measure of cognition. This digital intervention addresses the challenge of scaling effective multidomain lifestyle interventions for cognitive health and has the potential to improve risk behaviors and delay or reduce cognitive decline in older adults at-risk for AD. Robust trials of multi-domain risk reduction interventions have demonstrated an ability to reduce the rate of cognitive decline, multimorbidity, and cognitive impairment. However, scalability is limited by cost, intensity of the intervention, number and diversity of healthcare professionals required, and participant inconvenience. Thus, a lower cost, easier-to-disseminate version would have the potential for high impact on public health, and digital interventions hold great promise for addressing this need. Neurotrack?s digital cognitive health program modeled on the landmark FINGER protocol provides structured, semi-tailored support for behavioral change across multiple domains through a mobile app and on-demand health coaching. This Fast Track SBIR is designed to refine the digital platform (Phase I) and conduct a randomized controlled trial (Phase II). PHASE I ? Aim. Refine Neurotrack?s digital multi-domain lifestyle intervention interface and content delivery to optimize adoption, engagement, and adherence. User testing will provide information to improve design and delivery (? 80% of testers achieve 100% Task Success Rate), and the app will be replicated for delivery on Android devices (Android app passes 100% of functionality / bug checks.). PHASE II ? Aim 1. Determine the effect of a two-year digital multi-domain AD risk reduction intervention on composite risk for AD in older adults at risk of developing AD. Aim 2. Determine the effect on the rate of cognitive decline. Aim 3. Determine the effect on change in general health outcomes. The Digital Cognitive Multi-domain Alzheimer?s Risk Velocity (DC MARVEL) trial will include 200 at-risk adults age 45-64 randomized to a two-year Memory Health Program (MHP) or digital health education protocol control. Endpoints will be assessed at baseline, 4, 12, and 24 months. Milestones: At 24 months, between groups difference of 1) ? 2.0-pt on ANU-ADRI and 2) ? 3.3-pt on RBANS; and 3) change ? the minimal clinically important difference on biomarkers, functional measures, and behavioral / quality of life measures for MHP from baseline to 24 months. This Fast Track SBIR has the potential for high impact by determining whether a broadly disseminable digital program can slow cognitive decline in at-risk participants to ultimately delay or prevent AD onset.